1. Field of the Invention
The present invention relates to a method of calculating radiation and, in particular, relates to a method for calculating accurately and rapidly the distribution and intensity of radiation from a variety of energy sources irradiating radiation such as a thermal power plant, a nuclear fusion reactor, an engine, a fire and a bonfire, a recording medium therefor and a computer therefor.
2. Convention Art
As a device for analyzing flow and radiation field in a region where exoergic or convection occurs, a radiation flow analysis device as disclosed in JP-A-8-221386 (1996) was known.
In the above conventional art, the radiation and flow analysis is performed in such a manner that a mesh having high density is applied on a part of the region to be noted and on the other region a mesh having uniformly coarse density is applied so as to reduce calculation steps and calculation time therefor.
Radiation calculation methods such as DT (Discrete Transfer) method, ray tracing method, Monte Carlo method and zone method perform calculation of radiation energy exchange by causing to emit rays or photons from radiation elements such as calculation cells and wall face elements into or out of which radiation energy makes incident or irradiates.
Although, as in the above conventional example, the radiation flow analysis in some cases were performed by applying a mesh having a high density with regard to a part of the region to be noted, however, with regard to the other region a coarse mesh having the same size, in that a calculation cell was used regardless to whether the location is near or remote from the calculation cells and the wall face elements.
Therefore, it takes very long calculation time to calculate an energy exchange between a remote location covered by a coarse mesh and a noted cell.
Further, in the conventional radiation calculation method, since there were many non-influential cells for calculation in a location remote from a noted radiation element for radiation calculation, the calculation accuracy was low.